Work holding jaws for chucks



July 28, 1959 c. E. sTRAUss woRx hommeA JAws FOR cHucxs Filed June 25, 1958 anni. il. ,D 6-

7J i i5 INVENTOR (Zar/as ZS/*mzss ATTORNEY i July 28, 1959 v c. E. sTRAUss 2,896,958

' `WORK HOLDING JAWS FOR CHUCKS Filed June 25, 1958 2 Sheets-Sheet 2 Qi' y 31 ller. 7/31 INVENTOR Z alf/esl. Sirf/ass;

ATTORNEY United States' Patent Oice 1 2,896,958 wom( HoLDlNG JAWS FOR cHUcKs Charles E. Strauss, Santa Barbara, Calif. Application June z3,`195s,'seria1 No. 743,530

s claims. (Cl. 279-123) This invention relates to a chuck and particularly pertains to Work holding jaws for attachment to the master jaws of conventional chucks commonly employed in turret lathes.

The primary object of the invention is to provide working jaws having a wide range of adaptability for gripping engagement with cylindrical elements of various diameters with a considerable area of circumferential contact between the jaws and a cylindrical element engaged thereby.

The invention generally considered resides in the provision of an adaptor attachment to the master jaw of a chuck together with a work engaging jaw for positioning on the adaptor with the adaptor and jaw having cooperating interengaging means whereby the jaw may be fixed on the adaptor at various positions longitudinally thereof to dispose the gripping surface of the jaw in various spaced relation to the center of the chuck so as to accommodate the jaws for engagement with cylindrical elements of various diameters.

The invention 'further resides in a work engaging jaw having a series of arcuate -gripping surfaces of varying radii together with a mode of mounting the jaw on an adaptor so that any one of a series of gripping surfaces on the jaw may be presented to the work to be gripped, whereby a particular arcuate gripping surface may be selected for engagement with lthe cylindrical surface to conform thereto.

With the foregoing objects in view together lwith such other objects and advantages as may subsequently appear, the invention resides in the parts and in the combination, construction and arrangement of parts hereinafter described and claimed, and as illustrated by way of example in the accompanying drawings in which:

Fig. l is a view in front elevation of a chuck showing the invention as applied;

Fig. 2 is an enlarged detail in section and elevation as seen on the line 2 2 of Fig. l showing the manner of mounting jaw on an adaptor and of mounting the adaptor on the master jaw of a chuck;

Fig, 3 is a view in rear elevation of the chuck jaw depicted in Fig. 2, showing it detached;

Fig. 4 is a View in front elevation of a modified form of the chuck jaw;

Fig. 5 is a view in section and elevation as seen on the' line 5-5 of Fig. 4;

Fig. 6 is a View in elevation of an adaptor as constructed to receive the jaw shown in Figs. 4 and 5;

Fig. 7 is a ,view in cross section as seen on the line 7 7 of Fig. 6 showing the adaptor as applied to the master jaw of a chuck; and

Fig. 8 is a view in side elevation of the chuck shown in Fig. l illustrating' the mode of operation thereof in gripping an object to be worked.

Referring to the drawings more specifically wherein corresponding reference characters are employed to designate corresponding parts throughout the several views, A indicates generally a conventional chuck fitted with radially extendingv master jaws B adapted to be adjusted longitudinally and radially of the chuck A in the usual mannerby means not necessary to be here shown.

In carrying out the invention an adaptor 'C is xedly mounted on the master jaw B as by means of screws D. The adaptor C serves as a mounting for a demountable jaw E which jaw is designed to Abe supported on the.-

adaptor C at any one of several points along the length thereof and also to be adjusted and fixed on the adaptor C to present any one of the various sides of the jaw toward the inner end of the adaptor and thereby be presented toward a line extending axially of the chuck A, as will presently be described.

In the construction shown in Figs. l to 3 inclusive and also in Fig. 8, the jaw E comprises a metal block having parallel top and bottom faces a and b and having` four longitudinally concave arcuate sides c, d, e and f constituting independent work gripping surfaces. The faces c, d, e and f are here shown as formed with longitudinal V-grooves g for effecting engagement with corresponding contoured ribs h formed on a cylindrical element j to be engaged by the jaws E ras shown in Fig. 8 and in the manner set forth in United States Letters Patent No. 2,309,260. However the gripping faces of the jaws may be contoured in any suitable manner such as by forming them with any of the various types of serrations corn- 4 monly employed in chuck jaw construction. The arcuate faces c, d, e and f are respectively formed on arcs struck from radii of different lengths and which radii may be of any suitable dimensions, for example the face c may be formed on arc having a radius of two (2) inches, while the faces d, e and f may be formed respectively on radii of two and one-fourth (21A), two and one-half (2l/z) and` two and three-fourths (2%) inches. The opposed concave faces c and e extend on arcs the radii of which are struck from diametrically opposed points on a line leading through the axis of the jaw E, and the opposed concave faces e and f extend on arcs the radii of which are struck from diametrically opposed points on a line leading through the axis of the jaw perpendicular to the line from which the radii of the faces c and e are struck.

Interengaging means are provided on the adaptors C and jaws E for positioning the jaws E on the adaptors with either of the arcuate faces c, d, e and f presented toward the Work to be gripped by the jaws at the inner end of the adaptor. This means is here shown as embodying an arrangement of channels on the upper face of the adaptor C and a complementary arrangement of ribs on the bottom faces of the jaws E; each adaptor C having a central longitudinal channel 10 extending.

throughout the length thereof together with a series of spaced transverse channels 11 opening at the sides of the adaptor and intersecting the longitudinal channel 10 and which channels 10-11 are of rectangular cross section and correspondingly dimensioned and each jaw E having on its bottom face a series of four complementary equispaced radial ribs 12, 13, 14 and 15, which are coplanar and of rectangular cross section and dimensioned to slidably t the channels 10-11 on the adaptor. The outer ends of the ribs 12, 13, 14 and 15 terminate at the margins of the jaw. f

The radial ribs 12, 13, 14 and 15 intersect at their inner endswith the ribs 12-15 longitudinally opposed, as are the ribs 13-15 and with the axes 11i-m of the ribs 12-14 extending diametrally of the jaw in perpendicular relation to the axes m-.n ofthe jaws 13-15, as indicated in Fig. 3.

The opposed arcuate `faces c ande are here shown as formed on arcs the radii of which are struck from points on the axial line m-m spaced outwardly from the jaw and the opposed faces d and e are shown as formed on Patented July` 92s, 195el `ares .the radii` of which .aregstrucle from points .ony the axial line n n spaced outwardly from the jaw, whereby the axes of the ribs 12, 13, 14 and 15 intersect the arcuatelfacesuc, dgtegand ff-respectivelymidway ofthe: ends offsuch faces., 1

This relative Y arrangement` is `illustrated yin Fig.. 3 `as -to thesarc'uate face4 yf vwherein the radiusv of l such face-is 1indicatedfbyV the brokenline yr and the pointbf suohradiuson thecenter line -nV-nis indicated at .17, therfa'cesrcfd4 andebeingsimilarly delined. 10 'Ihegadaptor Chas a threaded screw receiving holev` 16;-at Ythe intersection of the axes-of the channels 10-11'- and. each of the vjaws E has an unthreaded laxialf bore 17 f toqreceivea .bolt 18 having a threaded end r19adapted= for. engagement withv any of therholes 16 and having a 15 head 20 engageable with the bottom of a recess 21 inl ther-top'face t of the jaw, such bolt being employed to tightly clampthe jaw on the adaptor with theseveral ribs onthe jaw engaged in certain of the channels -11 onlthe adaptor. i

In the operation of the invention as above described, the-adaptors C are vmounted on the master jaws B by seatingthern on such jaws and yattaching them Vthereto lby the screws D which are passed through openings 22 in 1the.adaptor and engaged with threaded openings 23 25 in .thevmaster jaws, which screws have heads 24 which seat on the -bottoms of recesses 25 in the adaptors. The jawsV E are mounted on the adaptors either before or after the latter are attached to the master jaws Vin the manner above-described; the several jaws being arranged onthe 30 several adaptors -with corresponding Varcuate gripping t faces ,thereof presented toward the inner ends of the adaptors as shownin Fig. l, the jaws being selected and selectively arranged according to the diarnetricalV dirnen-n sions of the work to be engaged thereby.- For example if 35 the work j to be engaged has a cylindrical surface to'be gripped extending on anarc the radius of which'fhas a length of two inches then a set `of jaws E isV selected wherein each jaw has an arcuate gripping VJface the radius of which is two inches and the'set'of jaws are mounted on `therseveral adaptors C and arranged thereon-with the appropriate arcuate gripping face presented to the portion of Vthe work to be lgrippedl in Yclose proximity thereto, each of the jaws E being located onits associated adaptor with the ribs 12, 13, 14 or 15 thereon lead- 45 ingfrom the forwardly presented gripping face, disposed inthe longitudinal channel 10 of the adaptor, andwith thethen transverse ribs on the jaw E engaged in the particular transverse channels 11 of the adaptor which will dispose the jaw in proximate spaced relation to the member to be gripped. The master gear Bis then adjusted in a usual manner to bring the assembly of jaws E 'into gripping engagement with the portion of the work v to be gripped.

In the form of the invention shown'in Figs.v 4 to 7 V55 inclusive, the adaptor CV and the jawV Eare designed to aord a greater number of gripping faces having arcs of'different radii than in the construction shown in Figs.

1 to3 inclusive. As here shown, the jawy Ehas a series of eightindependent arcuate faces s, t, u, v, w, x y vanal'z, 60 sai'dfaees` being formed on radiiV Vranging from ,two inches in length to three and three quarters inches in length with one-fourth inch'differential between adjacent arcuate faces. The bottom face of the jaw Eis formed with a series of equi-spaced radial ribs 26 with the axis 65 of leach of such Vribs extending on a radial plane leading fromV the center of the jaw through the arcuate faces intermediate the endsthereof.

The ladaptor CA in this instance has a central longitudi-V nal channel 27 in which is a'pair of bolt holes.28'-.28 70 for the reception of bolts by which the adaptor is fas tenedonto a master jaw,B1in.the manner before describedf The adaptor is also formed with a series of threaded screw receiving holes 29 spaced longitudinally' in Y the channel to receive a screwby which the jaw Eis 4 securely butremovably-attached-to'the adaptor in the manner before described, the jaw E having a central screw receiving opening 30 for theY reception of a screw which is passed through the jaw E and engaged with one of the holes 29.

Radiating from each of the holes 29 is a group of equispaced radial channels 31 adapted to snugly but removablyreceive .the several ribs. 26 yofA the jaw E shown in Figs. 4-5, any one of the channels 31 being capable of receiving vany oneof Vthevribs ldwh'ere'by the jaw may be seated in either of.v the groups of channels 31 to present either of the arcuate jaws thereon to the inner end of the adaptor.

The arcuate faces are here shown asfblank but are subject to being worked to provide gripping' surfaces according to requirements.

Manifestly the mode, of,operratiou of Ythe i construction shown -in Figs, 4 to 7inclusivevistheame as ,that Vde.- scribed with reference to the `construction shown iny Figs.` l`to 3'a11d-8;l Y Y While I have shown and described specicembodiments ofjth'e invention, Ido not limit myselfjtothe rexact details Vof'constructionjset forth, and the -invention emv braces suchA changes, modifications ,and equivalents of,

the parts and their formation and arrangement as come withinethe purview of the appended claims.

I claim:

1. A chuck jaw attachment` for the master jawy of aV chuck comprising an adaptor, meansforf connecting said adaptor to a master jaw, said adaptorhaving an upper -facewith channels therein, a ,jaw memberhaving a bottom face, ribs on said bottom face Vengageable in said v channels, saidjaw member also having an axial ,bolt

Vholea bolt in saidhole having threaded engagement with said adaptor,- and avplurality of longitudinally concave arcuate marginal work engaging faces on said jaw member Y adjacent -ofwhich extend onvarcs the radii of which are of, different lengths..

2. A chuck jaw attachment for the master jaw of'a chuckA-comprisingan adaptor, means for detachably connecting'said adaptor toa master jaw, said adaptor having lan elongated upper face having a plurality of groups oflcross c'hannelsthereim a jaw member having a ,bottomA face, radial ribs on said bottom face engageabley in'anyv one of the -groups of. channels on'said adaptor, means detachably connecting said jaw to said adaptor with said l ribs engaged in saidl channels, and a plurality of longitudiuallyconcave arcuate marginal work enga-ging faces on said jawy member adjacent of which'extend onarcs the radii of which are of different lengths.

3. In a chuck jaw attachment for the master jaw of a chuck, an adaptor having an elongated upper face having therein a pluralityr of lgroups of radially related channels and having an inner end, means for detachably: connecting said adaptor to a masterjaw, a jaw member having a bottom face,` a plurality of longitudinally'concave arcuate marginal work engaging faces onfsaid jaw member adjacent of -which extend on arcs the radii of whichfare offdiferent lengths, radial ribs on said bottom face engageable in any one of said groups of. channels,

there being one of said ribs associated with each of said arcuate faces the longitudinal center ofl Which'extends Ona plane leading mid-way of the ends of the associated arcuate face, saidribs being engageable with said channels to position said jaw with either of the arcuate mar-v ginal faces thereof -presented toward the inner end of` said adaptor, and means for detachably connecting said jaw to said adaptor at either'of said groups of radially related channels.

4. The structure called for in claim 3 in which said last namedmeans comprises a ,threaded holel in said adaptor at thecenter of eaoh of said groups of related channels, an axial bolt', receiving hole inv said jaw member, anda bolt passing through the'hole in said jaw member and screwed into enga-gement with a selected one of said threaded holes in said adaptor.

5. An attachment for the master jaw of a chuck comprising an adaptor having an upper face and an inner end, a jaw member having a bottom face and having a plurality of longitudinally concave arcuate marginal Work engaging faces, radial ribs on said bottom face, said adaptor having channels on its upper face for the reception of said radial ribs, and means lfor detachably connecting said jaw to said adaptor with said ribs and channels interengaged, said ribs and channels being arranged relative to each other and to the 'concave arcuate faces soV as to present an arcuate face in the direction of the inner end of said adaptor When said ribs and channels are intercngaged.

References Cited in the le of this patent UNITED STATES PATENTS 890,063 Jones June 9, 1908 1,033,547 Cornil July 23, 1912 1,531,377 Clarke Mar. 31, 1925 10 2,543,117 Mackmann Feb. 27, 1951 FOREIGN PATENTS 79,065 Denmark Mar. 28, 1955 

